青藏高原北缘地区高寒草甸土壤保持功能及其价值的实验研究

Soil conservation capacity of alpine meadow ecosystem and its economic value in the northern Qinghai-Tibetan Plateau

高寒草甸是青藏高原分布面积最大的草地类型,其土壤保持功能对于保护敏感而脆弱的青藏高原生态与环境具有重要的生态学意义.该文选取青藏高原北缘地区作为采样点,采用风洞实验方法,人为设计不同干扰方式,找出不同干扰方式下土壤风蚀率的变化规律,并以定量化方式揭示高寒草甸土壤保持功能的大小及其经济价值.通过实验得出:不同破坏程度和不同风速都会对风蚀率产生影响.一般情况下,土壤风蚀率随不同破坏程度和风速的增加而呈现出非线性的增加趋势.同时,随着风蚀现象的发生,土壤养分含量也出现不同程度的下降.最后,该文通过设置不同情景,对高寒草甸生态系统土壤保持功能进行价值评价,得出青藏高原高寒草甸仅土壤保持功能的经济价值就达1.5～4.6亿元a.

Alpine meadow is the largest grassland type in the Qinghai-Tibetan Plateau and its function of soil conservation is vital to protect the sensitive ecology and environment there. This paper designed different disturbance manners to discover the laws of soil erosion and their values by means of wind tunnel experiments at different speeds sampled in the northern Qinghai-Tibetan Plateau. From the results of wind tunnel experiment, it was found that both the different extent of destruction and varied wind speeds influence wind erosion. Their relations were non-linear. With the process of erosion, nutrients decreased to a certain degree. Finally, the direct value of the soil conservation capacity of scenic analysis. reached 1.5 × 10^8 -4.6×10^8￥ per year by means of scenic analysis.